1. Field of the Invention
The present invention relates to a weatherstrip for a sashless door in automotive vehicles, particularly to a weatherstrip which is capable of allowing water to drain from the space between the edge of the sashless door and the seal lip portion of the weatherstrip, and which also has high durability and maximal sealing characteristics between the window and the weatherstrip.
2. Description of the Prior Disclosure
Recently, there have been proposed and developed various weatherstrips which are applicable in sashless door type automotive vehicles which are capable of sealing the space between the window and the side panel of the vehicular body.
One such weatherstrip is illustrated in FIGS. 1 and 2. This conventional weatherstrip 4 is retained by an outer side roof rail and the roof support pillars of a sashless door type automotive vehicle 1 and is arranged in such a manner that the seal lip portion of the weatherstrip mates with upper and side edge portions of the inner window surface of the window 5 of a rear sashless door 2 and the inner window surface of the window 6 of a front sashless door 3. This prevents water trapped between the weatherstrip and the window from entering into the vehicular cabin. The weatherstrip 4 is secured on the outer roof rail and to the roof pillars through a retainer 10 and also is provided with a hollow seal portion 7 which mates with the upper and side edge portions of the windows 5 and 6. Further, the weatherstrip 4 is integrally formed with an extrusion molded portion 8 extending along the pillars and upper rail, and two die molded end portions 9 where the weatherstrip terminates at the front and rear door waist. This conventional weatherstrip has been disclosed in the Japanese Patent First Publication (Tokkai Showa) 60-219146. As set forth above, such weatherstrips are provided so as to prevent the entry of water, for example rainwater, water under pressure such as during car washing, or the like, into the vehicular cabin. However, some water tends to become trapped between the window edge 5a, the inner perimeter of the window surface 5b, and the hollow seal portion 7 during car washing or heavy rain.
The water that is trapped between the end portions of the window and the hollow seal lip portion drips into the vehicular cabin, when the door is opened in a condition where the corresponding window is fully closed.
In FIG. 3, another type of weatherstrip 20 which has a main seal lip portion 21a and a sub seal lip portion 21b formed on the hollow seal portion 21, is shown. Between the main seal lip portion 21a and the sub lip seal portion 21b, a groove 22 is defined. The groove 22 functions to forcibly capture rainwater or water during car washing, thereby preventing the water from entering between the mating portions with slightly inferior sealing properties between the weatherstrip and the window. This double lip seal type weatherstrip 20 is provided a retainer 10 which is secured by a fastening means, such as tapping screws on the outer roof rail and the pillars of the vehicular body in such a manner that the main seal lip portion 21a mates with the inner perimeter of the window surface 5b to a depth of substantially 20 mm, and the sub seal lip portion 21b mates with the edge portion 5a of the windows 5 and 6. Normally, suitable sealing material is inserted between the retainer 10 and the outer side roof rail 23 of the automotive vehicle 1. However, as shown in FIG. 3, however, in such double lip seal type weatherstrips, water tends to stay in the aperture between the inner perimeter of the window 5 surface 5b and the water capturing groove 22 defined by the pair of lips 21a and 21b. The structure of the double lip seal type weatherstrip is similar to that of the weatherstrip shown in FIG. 2. except for the groove 22. Although it is not shown in the drawings, the groove 22 extends along the edge portion of the door window under the condition of the window being closed, however the groove is so formed as to end at the die molded end portions 9 of the weatherstrip 20. As a result, the water is not drained outside of the vehicle, but remains trapped in the above mentioned aperture. Therefore, the trapped water can enter into the vehicular cabin, when the sashless door 5 is opened. In double lip seal type weatherstrips for the sashless door type automotive vehicles, an inner lip portion 25 extends inside of the vehicle. In order to gain greater sealing, the inner lip portion 25 mates with an outer periphery of a U-shaped garnish 26 which is made of synthetic resin and which engages with a flange portion connecting an outer side roof rail 23 and an inner side roof rail 24. Such a double lip seal type weatherstrip has been disclosed in the Japanese Utility Model First Publication (Jikkai Showa) 61-67258.
FIG. 4 shows the conventional connecting method suitable for sealing the space between the front window 6 and the rear window 5 in sashless door type automotive vehicles without center pillars. A center seal rubber 27 adheres to the forward facing edge portion of the rear window glass 5. In vehicles with center seal rubbers, a slight breach tends to be formed in the vicinity of the center rubbers 27 mating with the weatherstrip shown in FIGS. 2 and 3. This deteriorates the sealing performance of the weatherstrip at the point where the rear edge of the front window glass 6 opposes the front edge of the rear window glass 5. Specifically, in the dual lip seal type weatherstrips as shown in FIG. 3, the sealing performance of the weatherstrip is lowered due to the water capturing groove, and the breach of seal occurring where the center rubber meets the weatherstrip.